JP7753187B2 - Articles containing crosslinked guanidinyl-containing polymers and uses thereof - Google Patents

Description

Microorganisms are known to persist on surfaces for extended periods of time. Some of these organisms require only approximately 10 to 100 organisms for infection. Good hygiene practices, such as handwashing and surface disinfection, have been proven to eliminate or reduce the transmission of these pathogenic microorganisms, significantly impacting public health. Daily use of disinfectant cleaners containing quaternary ammonium compounds or alcohol-based cleaners is effective in killing most microorganisms; however, some bacteria, such as Clostridium difficile (C. difficile) spores, exist that are unaffected by such chemicals. While bleach and peracetic acid-based chemicals are often used to eliminate other persistent organisms, these chemicals are not frequently used due to their corrosive properties and associated health issues, such as skin and nasal irritation. Reducing the transmission of these organisms without the need for chemical disinfectants is highly desirable.

While articles such as wipes containing crosslinked polymers are known, many exhibit undesirable polymer wash-off, thereby resulting in inefficient manufacturing processes and reducing the effectiveness of such articles. Insufficient crosslinking of coating polymers can result in the leaving of undesirable polymer and crosslinker residues on surfaces that come into contact with such articles.

The present disclosure relates to articles, such as filters or wipes, containing cationic coatings and methods of using the articles. The cationic coatings include crosslinked guanidinyl-containing polymers. The coatings are not easily separated from the substrate. As a result, minimal or no residue of the cationic coating remains on the surface after cleaning, for example, with a wipe.

In one embodiment, an article includes a substrate and a cationic coating attached to the substrate, the cationic coating comprising a guanidinyl-containing polymer crosslinked on the substrate, wherein the guanidinyl-containing polymer has the following formula (I):
wherein R ³ is H, C ₁ -C ₁₂ (hetero)alkyl, C ₅ -C ₁₂ (hetero)aryl, or polymer; each R ⁴ is independently H, C _{1 -C 12 (hetero)alkyl, or C 5 -C 12} (hetero)aryl; each R ⁵ is H, C ₁ -C ₁₂ (hetero)alkyl, _{C 5} -C ₁₂ (hetero)aryl, or N(R ⁴ ) ₂ ; polymer is the remainder of an amino polymer chain; m is 1 or 2; and x is an integer of at least 1.
wherein the guanidinyl-containing polymer is crosslinked with an amine-reactive polyepoxy compound (eg, glycerol diglycidyl ether) having pendant —OH groups.

In certain preferred embodiments, the article is a wipe. The wipe is useful for removing microorganisms from a surface contaminated with the microorganisms and also for reducing recontamination of a cleaned surface with the removed microorganisms or reducing the transfer of the removed microorganisms to another surface. Advantageously, upon contact with an area of a surface contaminated with microorganisms, the wipe can remove at least 99 percent of the microorganisms in the area. The removed microorganisms adhere to the wipe, and when the wipe contacts a second surface or a previously cleaned surface, no more than 0.2 percent of the removed microorganisms are transferred from the wipe to the second surface.

In another embodiment, the method is a method for removing contaminants from a contaminated surface, the method comprising contacting an article in the form of a wipe with an area of the contaminated surface in the presence of a liquid, the contaminated surface being a solid surface.

As used herein, "polymer" includes homopolymers, copolymers, terpolymers, etc. "Polymer" in formula (I) refers to all portions of the guanidinyl-containing polymer excluding the x group of formula (I), or ^R3 (if it is the remainder of the amino polymer chain).

As used herein, the term "guanidinyl" refers to the group of the following formula: ^--NR.sup.3 --C( ^{.dbd.NR.sup.4} ) ^{-- NR.sup.4R.sup.5} .

As used herein, "alkyl" refers to a monovalent radical of an alkane and includes straight-chain, branched, and cyclic alkyl groups, and includes both unsubstituted and substituted alkyl groups. Unless otherwise specified, alkyl groups typically contain 1 to 20 carbon atoms, or 1 to 12 carbon atoms. Examples of "alkyl" as used herein include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, isobutyl, t-butyl, isopropyl, n-octyl, n-heptyl, ethylhexyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, and norbornyl. The term "heteroalkyl" refers to an alkyl containing 1 to 3 heteroatoms such as nitrogen, oxygen, or sulfur. The term "(hetero)alkyl" refers to both alkyl and heteroalkyl groups.

As used herein, "alkylene" refers to a divalent radical of an alkane and includes straight-chain, branched, and cyclic alkylene groups, and includes both unsubstituted and substituted alkylene groups. Unless otherwise specified, alkylene groups typically contain 1 to 20 carbon atoms. Examples of "alkylene" as used herein include, but are not limited to, methylene, ethylene, n-propylene, n-butylene, n-pentylene, isobutylene, t-butylene, isopropylene, n-octylene, n-heptylene, ethylhexylene, cyclopentylene, cyclohexylene, cycloheptylene, adamantylene, and norbornylene.

As used herein, "aryl" refers to a monovalent radical of an aromatic group containing 5 to 12 ring atoms, which may contain fused rings and may be saturated, unsaturated, or aromatic. Examples of aryl groups include carbocycles containing phenyl, naphthyl, biphenyl, phenanthryl, and anthracyl. The term "heteroaryl" refers to an aryl containing 1 to 3 heteroatoms such as nitrogen, oxygen, or sulfur, which may contain fused rings. Some examples of heteroaryl groups are pyridyl, furanyl, pyrrolyl, thienyl, thiazolyl, oxazolyl, imidazolyl, indolyl, benzofuranyl, and benzthiazolyl. The term "(hetero)aryl" refers to both aryl and heteroaryl groups.

As used herein, "arylene" refers to a divalent radical of an aromatic group containing 5 to 12 ring atoms, which may contain fused rings and may be saturated, unsaturated, or aromatic. Examples of carbocyclic arylene groups include carbocycles containing phenylene, naphthylene, biphenylene, phenanthrylene, and anthralene.

As used herein, "contact in the presence of a liquid" generally refers to contacting a wipe with a surface (e.g., a microbially contaminated surface, such as a surface contaminated with microorganisms) such that the wipe and/or surface are wetted with the liquid in the area where the surface and wipe contact each other. The liquid typically comprises at least 10 percent water by weight, and can comprise up to 100 percent water by weight, based on the total weight of the liquid.

As used herein, the term "bonded" means, with respect to a cationic coating that is bonded to a substrate (e.g., a guanidinyl-containing polymer in a cationic coating), that the cationic coating cannot be removed without destroying the substrate. For example, the cationic coating can be chemically attached to the substrate or crosslinked around the fibers of the substrate, such that the coating cannot be removed by stripping, dissolving in water or an organic solvent.

The term "microorganism" refers to bacteria (including gram-positive and gram-negative bacteria), fungi (e.g., yeast), molds, protozoa, viruses (including both non-enveloped and enveloped viruses), bacterial endospores, and the like, and combinations thereof. In some embodiments, the microorganism comprises a bacterial endospore.

As used herein, the term "comprising" and variations thereof do not have a limiting meaning when these terms appear in the description and claims. Such terms are understood to imply the inclusion of a described step or element, or group of steps or elements, but not the exclusion of any other step or element, or group of steps or elements. "Consisting of" means including and limiting to whatever precedes the phrase "consisting of." Thus, the phrase "consisting of" indicates that the listed elements are necessary or essential, and that no other elements may be present. "Consisting essentially of" means including any elements listed after the phrase, and is limited to other elements that do not interfere with or contribute to the action or function specified in this disclosure for those listed elements. Thus, the phrase "consisting essentially of" indicates that the listed elements are necessary or essential, but that other elements are optional and may or may not be present depending on whether they materially affect the action or function of the listed elements. Any element or combination of elements described herein with open-ended language (e.g., "comprising" and its derivatives) is considered to be further described with closed-ended language (e.g., "consisting of" and its derivatives) and partially closed-ended language (e.g., "consisting essentially of" and its derivatives).

The words "preferred" and "preferably" refer to embodiments of the present disclosure that may provide certain benefits, under particular circumstances. However, other claims may also be preferred, under the same or other circumstances. Moreover, the recitation of one or more preferred claims does not imply that other claims are not useful, and is not intended to exclude other claims from the scope of the present disclosure.

In this application, the terms "a," "an," and "the" are not intended to refer to only one entity, but include general classes for which specific examples may be used for illustration. The terms "a," "an," and "the" are used interchangeably with the term "at least one." The phrases "at least one of" and "including at least one of" following a list refer to any one of the items in the list, and any combination of two or more items in the list.

As used herein, the term "or" is generally used in its ordinary sense, including "and/or," unless the content clearly dictates otherwise.

The term "and/or" means one or all listed elements or a combination of any two or more of the listed elements.

Furthermore, all numbers herein are deemed to be modified by the term "about," and in certain embodiments, preferably by the term "exactly." As used herein, in connection with a measured quantity, the term "about" refers to the variation in the measured quantity that would be expected by one of ordinary skill in the art making the measurement and exercising a level of care commensurate with the purpose of the measurement and the precision of the measuring equipment used. As used herein, a "up to" number (e.g., up to 50) is inclusive of that number (e.g., 50).

Furthermore, herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range and the endpoints thereof (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

As used herein, the term "room temperature" refers to a temperature between 20°C and 25°C or between 22°C and 25°C.

The terms "in the range" or "within a range" (and similar expressions) include the endpoints of the stated range.

Groupings of alternative elements or embodiments disclosed herein should not be construed as limiting. Members of each group may be referred to and claimed individually or in any combination with other members of the group or other elements found in the group. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification shall be deemed to include the group as modified herein, and accordingly shall implement the full meaning of all Markush group descriptions used in the appended claims.

When a group occurs more than once in a formula described herein, each group is "independently" selected, whether specifically recited or not. For example, when there are two or more R groups in a formula, each R group is independently selected.

References throughout this specification to "one embodiment," "an embodiment," "certain embodiments," or "some embodiments" mean that the particular feature, structure, composition, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases in various places throughout this specification are not necessarily all referring to the same embodiment of the present invention. Furthermore, the particular features, structures, compositions, or characteristics may be combined in any suitable manner in one or more embodiments.

The above "Summary" of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present invention. The following description more particularly exemplifies exemplary embodiments. In several places throughout this application, guidance is provided through lists of examples. These examples may be used in various combinations. In each instance, the recited items serve only as a representative group and should not be interpreted as an exclusive list. Thus, the scope of the present disclosure should not be limited to the particular exemplary structures described herein, but extends to at least the structures described by the language of the claims and equivalents of those structures. Any elements actively described herein as alternatives may be expressly included in or excluded from the claims in any combination as desired. While various theories and possible mechanisms may be discussed herein, such discussion is not intended to limit the patentable subject matter in any way.

1 is a schematic side view of an exemplary embodiment of an article of the present disclosure. 1 is a graphical representation of the results of nonwoven sheets of example glycerol diglycidyl ether (GDGE) and comparative examples (butanediol diglycidyl ether (BUDGE), ethylene glycol diglycidyl ether (EDGE), and poly(ethylene glycol) diglycidyl ether (PEGDGE)) washed according to the "Wash-Off Assay," with percent coating washed-off results reported as the average of triplicate values. 1 is a graphical representation of the results of an example (GDGE) and a comparative example (BUDGE) nonwoven sheet washed according to the "Wash-Off Assay," with the percent coating washed-off results reported as the average of triplicate values. 1 is a graphical representation of the static binding capacity results of nonwoven sheets of an example (GDGE), comparative examples (BUDGE, EDGE, and PEGDGE), and an uncoated control washed according to the "Wash-Off Assay" and then tested according to the "Tartrazine Static Binding Capacity Assay." 1 is a graphical representation of microbial removal from surfaces and cross-contamination using an example (GDGE), a comparative example (BUDGE), and an uncoated control nonwoven sheet according to the "Test Method for Microbial Removal and Transfer of Contamination from Microbial Contaminated Surfaces," with the results reported as the average value obtained from triplicates. 1 is a graphical representation of microbial removal from surfaces and cross-contamination using an example (GDGE), a comparative example (BUDGE), and an uncoated control nonwoven sheet according to the "Test Method for Microbial Removal and Transfer of Contamination from Microbial Contaminated Surfaces," with the results reported as the average value obtained from triplicates.

The present disclosure relates to articles, such as filters or wipes, containing cationic coatings and methods of using the articles. The coated article includes a substrate and a cationic coating bonded to the substrate. The cationic coating includes a guanidinyl-containing polymer that is crosslinked and, optionally, also covalently bonded to the substrate.

In one embodiment, an article includes a substrate and a cationic coating attached to the substrate, the cationic coating comprising a guanidinyl-containing polymer crosslinked on the substrate, wherein the guanidinyl-containing polymer has the following formula (I):
wherein R ³ is H, C ₁ -C ₁₂ (hetero)alkyl, C ₅ -C ₁₂ (hetero)aryl, or polymer; each R ⁴ is independently H, C _{1 -C 12 (hetero)alkyl, or C 5 -C 12} (hetero)aryl; each R ⁵ is H, C ₁ -C ₁₂ (hetero)alkyl, _{C 5} -C ₁₂ (hetero)aryl, or N(R ⁴ ) ₂ ; polymer is the remainder of an amino polymer chain; m is 1 or 2; and x is an integer of at least 1.
wherein the guanidinyl-containing polymer is crosslinked with an amine-reactive polyepoxy compound (eg, glycerol diglycidyl ether) having pendant —OH groups.

In certain preferred embodiments, the article is a wipe. The wipe is useful for removing microorganisms from a surface contaminated with the microorganisms and also for reducing recontamination of a cleaned surface with the removed microorganisms or reducing the transfer of the removed microorganisms to another surface. Advantageously, upon contact with an area of a surface contaminated with microorganisms, the wipe can remove at least 99 percent of the microorganisms in the area. The removed microorganisms adhere to the wipe, and when the wipe contacts a second surface or a previously cleaned surface, no more than 0.2 percent of the removed microorganisms are transferred from the wipe to the second surface.

FIG. 1 is a schematic side view of an exemplary embodiment of an article 200 comprising a substrate 210 and a cationic coating layer 220 disposed on a first major surface of the substrate 210. The article 200 further comprises a coating layer 222 disposed on a second major surface of the substrate layer 210 opposite the first major surface of the substrate 210. In some embodiments, the coating layer 222 can comprise the same cationic coating composition used in the cationic coating layer 220, although this is not a requirement; the coating layer 222 can alternatively comprise other coating compositions. In certain embodiments, only one major surface of the substrate has a cationic coating layer disposed thereon. In other embodiments, the article comprises a cationic coating layer surrounding the substrate.

In some other embodiments, the cationic coating may be disposed on the surface of the substrate as well as distributed throughout at least a portion of the substrate. That is, the cationic coating may penetrate the substrate. For example, if the substrate is a sponge, the cationic coating may be on the surface of the substrate as well as distributed throughout all or any portion of the substrate. In other examples, if the substrate includes fibers, the cationic coating may surround the fibers or any portion of the fibers.

The cationic coating comprises a guanidinyl-containing polymer. The guanidinyl group can be located at any position in the polymer. In most embodiments, the guanidinyl group is part of a pendant group attached to the backbone of the polymer. However, in some embodiments, the guanidinyl group is part of the backbone of the polymer.

As used herein, the term "guanidinyl" refers to the group ^-NR3 -C(= ^NR4 ) ^-NR4R5 of the ^formula : When the guanidinyl group is part of a pendant group, the group ^R3 is hydrogen, _C1 - _C12 (hetero)alkyl, or _C5 - _C12 (hetero)aryl. Alternatively, ^R3 can refer to a polymer where the N to which it is attached is part of the backbone of the polymer chain, and the polymer is the remainder of an amino polymer chain. Each group ^R4 is independently hydrogen, _C1 - _C12 (hetero)alkyl, or _C5 - _C12 (hetero)aryl. The group ^R5 is hydrogen, _C1 - _C12 (hetero)alkyl, or _C5 - _C12 (hetero)aryl, or a group of the formula -N( ^R4 ) _2- . The guanidinyl group may be part of a biguanidinyl group of the formula -NR ³ -C(=NR ⁴ )-NR ⁴ -C(=NR ⁴ )-NR ⁴ R ⁵ , where R ³ , R ⁴ and R ⁵ are as defined above.

Most guanidinyl-containing polymers have two or more guanidinyl groups. The number of guanidinyl groups can vary depending on the method used to prepare the guanidinyl-containing polymer. For example, the number of guanidinyl groups can depend on the amino-containing polymer precursor (i.e., amino polymer precursor) selected for reaction with a suitable guanylating agent. In some embodiments, the variable x can be up to 10,000, up to 5,000, up to 1,000, up to 500, up to 100, up to 80, up to 60, up to 40, up to 20, or up to 10.

The guanidinyl-containing polymer of formula (I) is often the reaction product of an amino-containing polymer precursor (i.e., an amino polymer precursor) with a suitable guanylating agent.

In certain embodiments, articles of the present disclosure comprise at least 0.1 weight percent guanidinyl-containing polymer, based on the total weight of the article. In certain embodiments, articles of the present disclosure comprise up to 10 weight percent guanidinyl-containing polymer, based on the total weight of the article. This amount is typically used for wipes, although higher amounts may be used for filters.

Amino-Containing Polymer Precursors Amino-containing polymers used as precursor polymers (i.e., precursor amino polymers or simply amino polymers) for preparing guanidinyl-containing polymers of Formula (I) can be represented by the following Formula (II): polymer-N(R ³ )H. The amino-containing polymer can be a linear or branched polymer. However, as noted above, amino-containing polymers typically have many groups —N(R ³ )H, and Formula (II) shows only one for ease of discussion. The —N(R ³ )H group can be a primary or secondary amino group and can be part of a pendant group or part of the backbone of the amino polymer precursor. The amino-containing polymer precursor can be synthetic or a naturally occurring biopolymer. Suitable amino-containing polymer precursors can be prepared using amino-containing monomers by chain-growth or step-growth polymerization procedures. These monomers can also be copolymerized with other monomers that do not have an amino acid group, if desired. Additionally, amino-containing polymers can be obtained by grafting primary or secondary amine groups using appropriate grafting techniques.

In some embodiments, useful amino-containing polymer precursors are water-soluble or water-dispersible polyamines. As used herein, the term "water-soluble" refers to a material that can be dissolved in water. The solubility is typically at least 0.1 grams per milliliter of water. As used herein, the term "water-dispersible" refers to a material that is not water-soluble but can be emulsified or suspended in water.

Various combinations of amino-containing polymer precursors may be used if desired.

Examples of amino-containing polymer precursors prepared by chain growth polymerization suitable for use include, but are not limited to, polyvinylamine, poly(N-methylvinylamine), polyallylamine, polyallylmethylamine, polydiallylamine, poly(4-aminomethylstyrene), poly(4-aminostyrene), poly(acrylamide-co-aminopropylacrylamide), and poly(acrylamide-co-aminoethyl methacrylate).

Examples of amino-containing polymer precursors suitable for use prepared by step-growth polymerization include, but are not limited to, polyethyleneimine, polypropyleneimine, polylysine, polyaminoamide, and polydimethylamine-epichlorohydrin-ethylenediamine.

Other useful amino-containing polymer precursors having primary or secondary amino end groups include, but are not limited to, dendrimers (hyperbranched polymers) formed from polyamidoamine (PAMAM) and polypropyleneimine. Exemplary dendrimer materials formed from PAMAM are commercially available from Aldrich Chemical (Milwaukee, WI) under the tradename "STARBURST (PAMAM) Dendrimers" (e.g., Generation 0 having 4 primary amino groups, Generation 1 having 8 primary amino groups, Generation 2 having 16 primary amino groups, Generation 3 having 32 primary amino groups, and Generation 4 having 64 primary amino groups). Dendrimer materials formed from polypropyleneimine are commercially available from Aldrich Chemical under the trademark designation "DAB-AM." For example, DAB-Am-4 is a generation 1 polypropyleneimine tetraamine dendrimer having four primary amino groups, DAB-Am-8 is a generation 2 polypropyleneimine octaamine dendrimer having eight primary amino groups, DAB-Am-16 is a generation 3 polypropyleneimine hexadecaamine dendrimer having 16 primary amino groups, DAB-Am-32 is a generation 4 polypropyleneimine dotriacontaamine dendrimer having 32 primary amino groups, and DAB-Am-64 is a generation 5 polypropyleneimine tetrahexacontaamine dendrimer having 64 primary amino groups.

Examples of suitable amino-containing polymer precursors that are biopolymers include chitosan and starch grafted with reagents such as methylaminoethyl chloride.

Still other examples of amino-containing polymer precursors include polyacrylamide homo- or copolymers and amino-containing polyacrylate homo- or copolymers prepared with a monomer composition containing amino-containing monomers such as aminoalkyl (meth)acrylates, (meth)acrylamidoalkylamines, and diallylamine.

For some articles, preferred amino-containing polymer precursors (i.e., amino polymer precursors or simply amino polymers) include polyaminoamides, polyamidoamines, polyethyleneimines, polypropyleneimines, polyvinylamines, polyallylamines, polydiallylamines, and mixtures thereof.

In certain embodiments, the amino-containing polymer precursor is polyethyleneimine.

Suitable commercially available amino-containing polymer precursors include polyamidoamines available under the tradename ANQUAMINE (e.g., ANQUAMINE 360, 401, 419, 456, and 701) from Air Products and Chemicals (Allentown, Pa.), polyethyleneimine polymers available under the tradename LUPASOL (e.g., LUPASOL FG, PR 8515, Waterfree, P, and PS) from BASF Corporation (Resselaer, NY), polyethyleneimine polymers such as those available under the tradename CORCAT P-600 from EIT Company (Lake Wylie, SC), and polyamidoamines available from Cognis under the tradename VERSAMID series of resins formed by reacting dimerized unsaturated fatty acids with alkylene polyamines. Examples of suitable polyamide resins include, but are not limited to, polyamide resins such as those available from Polyethylene Glycerol Corporation (Cincinnati, Ohio).

Guanylating Agents Guanidinyl-containing polymers can be prepared by reacting an amino-containing polymer precursor (i.e., an amino polymer precursor) with one or more guanylating agents. The number of amino groups available for guanylation (and crosslinking) can be determined by the amine equivalent weight of the amino-containing polymer precursor, or the polymer repeat unit. Such amino groups can be primary, secondary, tertiary, or even quaternary.

Typically, at least 0.1 mol%, at least 0.5 mol%, at least 1 mol%, at least 2 mol%, at least 10 mol%, at least 20 mol%, at least 30 mol%, at least 40 mol%, or at least 50 mol% of the amino groups in the amino-containing polymer precursor react with the guanylating agent. Up to 95 mol%, up to 90 mol%, up to 80 mol%, up to 70 mol%, up to 60 mol%, up to 50 mol%, or up to 25 mol% of the amino groups can react with the guanylating agent. For example, the guanylating agent can be used in an amount sufficient to functionalize 0.1 to 95 mol%, 0.5 to 90 mol%, 1 to 90 mol%, 1 to 80 mol%, 1 to 60 mol%, 2 to 50 mol%, or 2 to 25 mol% of the amino groups in the amino-containing polymer. Typically, primary amino groups react with the guanylating agent, but some secondary amino groups may also react.

There are unreacted amino groups from the amino-containing polymer precursor remaining in the guanidinyl-containing polymer to allow for crosslinking.

In certain embodiments, the amino polymer is polyethyleneimine and no more than 25 mole percent (or less) of the amino groups of the amino polymer are functionalized with guanidinyl groups. In certain embodiments, the amino polymer is polyethyleneimine and no more than 20 mole percent (or less) of the amino groups of the amino polymer are functionalized with guanidinyl groups. In certain embodiments, the amino polymer is polyethyleneimine and no more than 15 mole percent (or less) of the amino groups of the amino polymer are functionalized with guanidinyl groups.

Various combinations of guanylating agents may be used if desired.

Known guanylating agents for reaction with amino-containing polymer precursors include, but are not limited to, cyanamide, O-alkylisourea salts such as O-methylisourea sulfate, O-methylisourea hydrogensulfate, O-methylisourea acetate, O-ethylisourea hydrogensulfate, and O-ethylisourea hydrochloride; chloroformamidine hydrochloride; 1-amidino-1,2,4-triazole hydrochloride; 3,5-dimethylpyrazole-1-carboxamidine nitrate; pyrazole-1-carboxamidine hydrochloride; N-amidinopyrazole-1-carboxamidine hydrochloride; and carbodiimides such as dicyclohexylcarbodiimide, N-ethyl-N'-(3-dimethylaminopropyl)carbodiimide, and diisopropylcarbodiimide.

Amino-containing polymer precursors can also be acylated with guanidino-functional carboxylic acids, such as guanidinoacetic acid and 4-guanidinobutyric acid, in the presence of an activating agent such as EDC (N-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride) or EEDQ (2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline).

Additionally, guanidinyl-containing polymers can be prepared by alkylation with chloroacetone guanylhydrazone, as described in U.S. Pat. No. 5,712,027 (Ali et al.).

Guanylating agents for the preparation of biguanide-containing polymers include sodium dicyanamide, dicyanodiamide, and substituted cyanoguanidines such as ^N3 -p-chlorophenyl- ^N1 -cyanoguanidine, ^N3 -phenyl- ^N1 -cyanoguanidine, ^N3 -α-naphthyl- ^N1 -cyanoguanidine, ^N3 -methyl-N1-cyanoguanidine, ^N3 , ^N3 -dimethyl- ^N1 -cyanoguanidine, N3-(2-hydroxyethyl) ^{-N1 -} cyanoguanidine, and ^N3 -butyl- ^N1 -cyanoguanidine. Alkylene and arylene biscyanoguanidines can be utilized to prepare biguanide-functional polymers by chain extension reactions. The preparation of cyanoguanidines and biscyanoguanidines is described in Rose, F. L., "Cyanoguanidines and Biscyanoguanidines: A Novel Approach to the Preparation of Biguanide-Functional Polymers," by Rose, F. L., "Cyanoguanidines and Biscyanoguanidine ... and Swain, G. J. Chem Soc., 1956, pp. 4422-4425. Other useful guanylating reagents are described by Alan R. Katritzky et al., Comprehensive Organic Functional Group Transformation, Vol. 6, p. 640.

The guanidinyl-containing polymer formed by the reaction of the amino-containing polymer precursor with the guanylating agent has pendant or catenary guanidinyl groups of formula (III).

In formula (III), the groups ^R3 , ^R4 , and ^R5 and the variable m are as defined above. The wavy line attached to the N( ^R3 ) group indicates the point at which the group is attached to the remainder of the polymeric material. In most embodiments, i.e., when ^R3 is not a polymer, the group of formula (III) is a pendant group of the guanidinyl-containing polymer.

Optional Ligands In some embodiments, it may be advantageous to react the amino-containing polymer precursor to provide other ligands or groups in addition to the guanidinyl-containing group. For example, it may be useful to include hydrophobic, ionic, or hydrogen-bonding ligands. This may be particularly advantageous for removing certain microorganisms during wiping of a microbially contaminated surface.

Additional ligands can be readily incorporated into amino-containing polymers by alkylation or acylation procedures well known in the art. For example, the amino groups of amino-containing polymer precursors can be reacted using halide, sulfonate, and sulfate substitution reactions or using epoxide ring-opening reactions. Alkylating agents useful for these reactions include, for example, dimethyl sulfate, butyl bromide, butyl chloride, benzyl bromide, dodecyl bromide, 2-chloroethanol, bromoacetic acid, 2-chloroethyltrimethylammonium chloride, styrene oxide, glycidyl hexadecyl ether, glycidyl trimethylammonium chloride, and glycidyl phenyl ether. Useful acylating agents include, for example, acid chlorides and anhydrides such as benzoyl chloride, acetic anhydride, succinic anhydride, and decanoyl chloride, and isocyanates such as trimethylsilyl isocyanate, phenyl isocyanate, butyl isocyanate, and butyl isothiocyanate. In such embodiments, 0.1 to 20 mol %, preferably 2 to 10 mol %, of the amino groups of the amino-containing polymer precursor may be alkylated and/or acylated.

Crosslinking Agents and Methods of Making Articles The guanidinyl-containing polymer can be crosslinked. The amino-containing polymer precursor can be crosslinked prior to reaction with the guanylating agent. Alternatively, the guanidinyl-containing polymer can be crosslinked after reaction with the guanylating agent by reacting the remaining amino groups from the amino-containing polymer precursor with a crosslinking agent.

Suitable crosslinkers include amine-reactive polyepoxy compounds (e.g., di- and tri-epoxy compounds) with pendant -OH groups. Examples include glycerol diglycidyl ether, sorbitol diglycidyl ether, diglycerol diglycidyl ether, diglycerol triglycidyl ether, pentaerythritol diglycidyl ether, pentaerythritol triglycidyl ether, trimethylolpropane diglycidyl ether, and trimethylolethane diglycidyl ether. Various combinations of crosslinkers may be used if desired. A preferred crosslinker is glycerol diglycidyl ether.

Typically, the guanylated amino polymer is applied to a substrate (e.g., coated onto a substrate) in a liquid (e.g., water) and allowed to dry. Upon drying down, the guanylated amino polymer is crosslinked. In certain embodiments, the substrate is then washed to remove any uncrosslinked polymer. Details of such procedures can be found in the Examples section.

U.S. Patent Nos. 9,758,547 (Rasmussen et al.) and 10,087,405 (Swanson et al.) describe the use of guanidinyl-containing polymers crosslinked using butanediol diglycidyl ether (BUDGE) and ethylene glycol diglycidyl ether (EDGE) around nonwoven fibers. Although these materials were washed before use, subsequent experiments showed extensive polymer washoff. The cationic coatings of the present disclosure, with their distinct crosslinking chemistry, demonstrate significantly reduced washoff compared to coatings containing BUDGE or EDGE crosslinkers. The lower residual levels of polymer in the leachate/extractables enable a reduced-cost manufacturing route by eliminating the washing steps typically used to make commercial products. Higher volumes of articles can be prepared using less input coating material, further reducing manufacturing costs. Additionally, the articles of the present disclosure are more suitable for use in the food service industry, which requires low levels of residual ingredients for direct and indirect food contact surfaces.

Typically, at least 5 mol%, at least 10 mol%, or at least 15 mol% of the amino groups of the amine-containing polymer precursor react with the crosslinker (whether before or after guanylation of the precursor). Up to 95 mol%, up to 90 mol%, up to 80 mol%, up to 70 mol%, up to 60 mol%, up to 50 mol%, up to 40 mol%, or up to 30 mol% of the amino groups of the amine-containing polymer precursor react with the crosslinker (whether before or after guanylation of the precursor).

The number of amino groups available for crosslinking (guanylation) can be determined by the amine equivalent weight of the amino-containing polymer precursor or polymer repeat unit. Such amino groups can be primary, secondary, tertiary, or even quaternary. Therefore, both the crosslinked and guanylated percentages are calculated based on the original amine equivalent weight. Those skilled in the art can determine the maximum value of each depending on the amino polymer structure. For example, in polyethyleneimine (PEI), where 25% of the amine groups are tertiary, only 75% of the amine groups (primary and secondary) are available for guanylation and crosslinking. If all primary amines are guanylated prior to crosslinking, only secondary amines remain for crosslinking.

Substrates, Articles, and Methods of Use Substrates, articles, and methods of use of such articles can be found, for example, in US Pat. Nos. 9,758,547 (Rasmussen et al.) and 10,087,405 (Swanson et al.).

Articles (e.g., wipes and filters) are provided that include a substrate and a cationic coating disposed on a surface of the substrate, distributed throughout at least a portion of the substrate, or both. The cationic coating comprises a guanidinyl-containing polymer that is bonded to the substrate through crosslinks and, optionally, grafted (i.e., covalently bonded) to the substrate.

In certain embodiments, the substrate is selected from fibers, particles, glass bubbles, membranes, sponges, woven fabrics, nonwoven fabrics, and combinations thereof.

In certain embodiments, the substrate is non-porous.

In certain embodiments, the substrate is porous. In such embodiments, the cationic coating is disposed on a surface of the porous substrate, distributed throughout at least a portion of the porous substrate, or both. Examples of porous substrates include sponges, woven fabrics, nonwoven fabrics, or combinations thereof.

In certain embodiments, the guanidinyl-containing polymer is contacted with the substrate prior to crosslinking and crosslinked in the presence of the substrate. If the substrate comprises fibers (e.g., the substrate comprises a woven or nonwoven fabric), the crosslinked guanidinyl-containing polymer can surround the fibers. The fibers and the crosslinked guanidinyl-containing polymer can be mixed so that they are inseparable by techniques such as peeling or dissolving, or by any other technique without destroying the wipe.

In certain embodiments, the substrate is formed of a material selected from poly(meth)acrylates, poly(meth)acrylamides, polyolefins, poly(isoprene), poly(esters), poly(butadienes), fluorinated polymers, chlorinated polymers, polyamides, polyimides, polyethers, poly(ether sulfones), poly(sulfones), poly(vinyl acetate), copolymers of vinyl acetate, poly(phosphazenes), poly(vinyl esters), poly(vinyl ethers), poly(vinyl alcohols), poly(carbonates), polyurethanes, cellulosic materials, and combinations thereof.

During use, upon contact with a target biological species, a complex is formed comprising the guanidinyl-containing polymer and the target biological species.

The target biological species can be a near-neutral or negatively charged biological species. In certain embodiments, the target biological species is selected from a biopolymer and a microbial species. In certain embodiments, the biopolymer is selected from a protein, an enzyme, a nucleic acid, an endotoxin, and combinations thereof. In certain embodiments, the biological species is selected from a bacterium, a virus, a cell, cell debris, a spore, and combinations thereof. In certain embodiments, the cell is selected from a prokaryote, a eukaryote, and combinations thereof. In certain embodiments, the biological species is derived from a cell culture or fermentation process. In certain embodiments, the spore comprises a bacterial endospore.

In certain embodiments, the article is a wipe. Such a wipe can be used in a method for removing contaminants. In certain embodiments, the method for removing contaminants from a contaminated surface comprises contacting the wipe with an area of the contaminated surface in the presence of a liquid, wherein the contaminated surface is a solid surface. The liquid can include water, a water-miscible organic solvent, or a mixture thereof.

In certain embodiments, the contaminants are microorganisms. In certain embodiments, at least 99 percent of the microorganisms are removed from the area.

In certain embodiments, the article, when contacted with an area of a surface contaminated with microorganisms in the presence of a liquid and then contacted with a second surface, transfers no more than 0.2 percent of the microorganisms from the article to the second surface.

In certain embodiments, the article is a filter that can be used in standard filtration methods.

Embodiments Embodiment 1 is an article comprising a substrate and a cationic coating bound to the substrate, the cationic coating comprising a guanidinyl-containing polymer crosslinked on the substrate, wherein the guanidinyl-containing polymer has the following formula (I):
wherein R ³ is H, C ₁ -C ₁₂ (hetero)alkyl, C ₅ -C ₁₂ (hetero)aryl, or polymer; each R ⁴ is independently H, C _{1 -C 12 (hetero)alkyl, or C 5 -C 12} (hetero)aryl; each R ⁵ is H, C ₁ -C ₁₂ (hetero)alkyl, _{C 5} -C ₁₂ (hetero)aryl, or N(R ⁴ ) ₂ ; polymer is the remainder of an amino polymer chain; m is 1 or 2; and x is an integer of at least 1.
wherein the guanidinyl-containing polymer is crosslinked with an amine-reactive polyepoxy compound having pendant --OH groups.

Embodiment 2 is the article of embodiment 1, wherein the guanidinyl-containing polymer is crosslinked by reaction of at least 5 mol % (at least 10 mol %, or at least 15 mol %) of the amino groups of the amino polymer precursor with an amine-reactive polyepoxy compound having pendant —OH groups.

Embodiment 3 is the article of embodiment 1 or 2, wherein the guanidinyl-containing polymer is crosslinked by reaction of up to 95 mol% (up to 90 mol%, up to 80 mol%, up to 70 mol%, up to 60 mol%, up to 50 mol%, up to 40 mol%, or up to 30 mol%) of the amino groups of the amino polymer precursor with an amine-reactive polyepoxy compound having pendant -OH groups.

Embodiment 4 is the article of any one of embodiments 1 to 3, wherein the amine-reactive polyepoxy compound having pendant -OH groups is selected from the group consisting of glycerol diglycidyl ether, sorbitol diglycidyl ether, diglycerol diglycidyl ether, diglycerol triglycidyl ether, pentaerythritol diglycidyl ether, pentaerythritol triglycidyl ether, trimethylolpropane diglycidyl ether, trimethylolethane diglycidyl ether, and combinations thereof.

Embodiment 5 is the article of embodiment 4, wherein the amine-reactive polyepoxy compound having pendant -OH groups is glycerol diglycidyl ether.

Embodiment 6 is the article of any one of embodiments 1 to 5, wherein the guanidinyl-containing polymer is crosslinked on and covalently bonded to the substrate.

Embodiment 7 is the article of any one of embodiments 1 to 6, wherein at least 0.1 mol% (at least 0.5 mol%, at least 1 mol%, at least 2 mol%, at least 10 mol%, at least 20 mol%, at least 30 mol%, at least 40 mol%, or at least 50 mol%) of the amino groups of the amino polymer precursor are functionalized with guanidinyl groups.

Embodiment 8 is the article of any one of embodiments 1 to 7, wherein up to 95 mol% (up to 90 mol%, up to 80 mol%, up to 70 mol%, up to 60 mol%, up to 50 mol%, or up to 25 mol%) of the amino groups of the amino polymer precursor are functionalized with guanidinyl groups.

Embodiment 9 is the article of any one of embodiments 1 to 8, wherein x is at most 10,000, at most 5,000, at most 1,000, at most 500, at most 100, at most 80, at most 60, at most 40, at most 20, or at most 10.

Embodiment 10 is the article of any of embodiments 1 to 9, wherein the group R ³ refers to hydrogen, C ₁ -C ₁₂ (hetero)alkyl, or C ₅ -C ₁₂ (hetero)aryl.

Embodiment 11 is the article of any one of embodiments 1 to 10, wherein the amino polymer is selected from the group consisting of polyaminoamide, polyamidoamine, polyethyleneimine, polypropyleneimine, polyvinylamine, polyallylamine, polydiallylamine, and mixtures thereof.

Embodiment 12 is the article of embodiment 11, wherein the amino polymer is polyethyleneimine.

Embodiment 13 is the article of embodiment 12, wherein no more than 25 mole percent (or less) of the amino groups of the polyethyleneimine precursor are functionalized with guanidinyl groups.

Embodiment 14 is the article of embodiment 13, wherein no more than 20 mole percent (or less) of the amino groups of the polyethyleneimine precursor are functionalized with guanidinyl groups.

Embodiment 15 is the article of embodiment 14, wherein no more than 15 mole percent (or less) of the amino groups of the polyethyleneimine precursor are functionalized with guanidinyl groups.

Embodiment 16 is the article of any one of embodiments 1 to 15, wherein the guanidinyl group of the amino polymer is pendant from the amino polymer chain.

Embodiment 17 is the article of any one of embodiments 1 to 15, wherein the guanidinyl group of the amino polymer is within the amino polymer chain.

Embodiment 18 is the article of any one of embodiments 1 to 17, wherein the guanidinyl-containing polymer is a reaction product of a guanylation agent and an amino-containing polymer precursor.

Embodiment 19 is the article of any one of embodiments 1 to 18, wherein the guanidinyl-containing polymer is present in an amount of at least 0.1 weight percent, based on the total weight of the article.

Embodiment 20 is the article of any one of embodiments 1 to 19, wherein the guanidinyl-containing polymer is present in an amount of up to 10 weight percent, based on the total weight of the article (in the case of wipes, although higher amounts may be used for filters).

Embodiment 21 is the article of any one of embodiments 1 to 20, wherein the substrate is selected from fibers, particles, glass bubbles, membranes, sponges, woven fabrics, nonwoven fabrics, and combinations thereof.

Embodiment 22 is an article described in any one of embodiments 1 to 21, wherein the substrate is non-porous.

Embodiment 23 is an article described in any one of embodiments 1 to 21, wherein the substrate is porous.

Embodiment 24 is the article of embodiment 23, wherein the cationic coating is disposed on a surface of the porous substrate, distributed throughout at least a portion of the porous substrate, or both.

Embodiment 25 is an article described in embodiment 23 or 24, wherein the porous substrate comprises a sponge, a woven fabric, a nonwoven fabric, or a combination thereof.

Embodiment 26 is the article of embodiment 25, wherein the substrate comprises a woven or nonwoven fabric, includes fibers, and the cross-linked guanidinyl polymer surrounds at least some of the fibers.

Embodiment 27 is the article of any one of embodiments 1 to 26, wherein the substrate is formed of a material selected from poly(meth)acrylates, poly(meth)acrylamides, polyolefins, poly(isoprene), poly(butadiene), fluorinated polymers, chlorinated polymers, polyamides, polyimides, polyethers, poly(ether sulfones), poly(sulfones), poly(vinyl acetate), copolymers of vinyl acetate, poly(phosphazenes), poly(vinyl esters), poly(vinyl ethers), poly(vinyl alcohols), poly(carbonates), poly(esters), polyurethanes, cellulosic materials, and combinations thereof.

Embodiment 28 is the article of any one of embodiments 1 to 27, wherein upon contact with a target near a neutral or negatively charged biological species, a complex is formed comprising the guanidinyl-containing polymer and the target biological species.

Embodiment 29 is the article described in embodiment 28, wherein the target biological species is selected from biopolymers and microbial species.

Embodiment 30 is the article described in embodiment 29, wherein the biopolymer is selected from proteins, enzymes, nucleic acids, endotoxins, and combinations thereof.

Embodiment 31 is the article of embodiment 29, wherein the target biological species is selected from bacteria, viruses, cells, cell debris, spores, and combinations thereof.

Embodiment 32 is the article of embodiment 31, wherein the cells are selected from prokaryotes, eukaryotes, and combinations thereof.

Embodiment 33 is the article of embodiment 31 or 32, wherein the biological species is derived from a cell culture or fermentation process.

Embodiment 34 is the article of embodiment 31, wherein the spores comprise bacterial endospores.

Embodiment 35 is an article according to any one of embodiments 23 to 34, which is a filter.

Embodiment 36 is the article described in any one of embodiments 23 to 34, which is a wipe.

Embodiment 37 is a method for removing contaminants from a contaminated surface, the method comprising contacting an article described in embodiment 36 with an area of the contaminated surface in the presence of a liquid, wherein the contaminated surface is a solid surface.

Embodiment 38 is the method of embodiment 37, wherein the liquid comprises water, a water-miscible organic solvent, or a mixture thereof.

Embodiment 39 is the method of embodiment 37 or 38, wherein the contaminant is a microorganism.

Embodiment 40 is the method of embodiment 39, in which at least 99 percent of microorganisms are removed from the area.

Embodiment 41 is a method according to any one of embodiments 37 to 40, wherein the article, when contacted with an area of a surface contaminated with microorganisms in the presence of a liquid and then contacted with a second surface, transfers 0.2 percent or less of the microorganisms from the article to the second surface.

The objects and advantages of the present disclosure are further illustrated by the following examples, although the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit the present disclosure.

Unless otherwise noted, all parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, and all reagents used in the examples were obtained or available from general chemical suppliers such as, for example, Sigma-Aldrich, St. Louis, MO, or can be synthesized by conventional methods. The following abbreviations are used in this section: mL = milliliter, min = minute, h = hour, sec = second, g = gram, mg = milligram, m = meter, centimeter = cm, mm = millimeter, μm = micrometer or micron, °C = degrees Celsius, °F = degrees Fahrenheit, N = Newton, oz = ounce, mW/ ^cm2 = milliwatts per square centimeter. Unless otherwise noted, all parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight.

Test Methods Wash-Off Assay Three (pre-weighed) GPEI-coated nonwoven sheets (10 inches (25.4 centimeters (cm)) x 12 inches (30.5 cm)) were placed in a 1000 milliliter (mL) polypropylene bottle. Each sheet was prepared by the same exemplary method. Deionized water (800 mL) was added to the bottle, and the bottle was capped. For the first washing cycle, the bottle was placed on an orbital shaker (Lab-Line Instruments Incorporated, Melrose Park, IL) at 150 revolutions per minute (rpm) for 15 minutes. The water was then discarded and replaced with fresh deionized water. The washing cycle was repeated two more times using fresh deionized water for each washing cycle. After the three water washing cycles, the nonwoven sheets were removed from the bottle and dried at 110°C for 30 minutes. Each washed and dried sheet was weighed and the amount of coating remaining on the sheet was calculated. The "percentage of coating washed off" was calculated for each sheet according to Equation 1 (where "A" = "calculated amount of coating on the sheet before the washing procedure" and "B" = "calculated amount of coating on the sheet after the washing and drying procedure").
Equation 1: Percentage of coating washed off = 100 ^* [1 - (B/A)].

The average value (n=3) of the "percentage of coating washed off" was determined using the standard deviation.

Tartrazine Static Binding Capacity Assay. Tartrazine (5 mL of a 1.0 milligram per milliliter (mg/mL) solution in milliQ water) was added to a 15 mL conical tube containing a 25 mm (diameter) disk from a coated nonwoven sheet. Samples were incubated at room temperature for 22 hours while rotating on a tube revolver (Thermo Scientific; Waltham, MA) set at 20 rpm. Ten-fold dilutions of the supernatant were prepared in a Costar 96-well assay plate (Corning Incorporated, Corning, NY) containing MilliQ water and transferred (150 microliters) to a 96-well clear UV-STAR microplate (Greiner Bio-One North America Incorporated, Monroe, NC). A tartrazine standard series was prepared by two-fold dilution from 100 micrograms/mL to 0.78 micrograms/mL using milliQ water. The standards were added (150 microliters) to the microplate containing the diluted samples. A water-only control was added as the standard (0 micrograms/mL tartrazine) and blank. Absorbance (wavelengths of 255 nanometers (nm) and 425 nm) was measured using a SPECTRAMAX M5 plate reader (Molecular Devices, San Jose, CA). The standard curve (absorbance at 255 nm) was used to determine the tartrazine static binding capacity (SBC) of the coated nonwoven fabric discs by calculating the total amount of tartrazine bound to the disc by dividing the surface area of the disc (surface area of a 2.5 cm diameter disc = 4.91 ^cm ). SBC was reported as the average value from three replicates. This test provides an indication of the amount of polymer coated onto the substrate.

Test Method for Removal of Microorganisms and Transfer of Contaminants from Microbially Contaminated Surfaces The test method was performed as described in U.S. Pat. No. 10,087,405 (Swanson et al.) using four times the volume of distilled and sterile water used to wet each wipe.

Preparatory Example 1. 25% Guanylated Polyethyleneimine (25% G-PEI)
Polyethyleneimine (PEI), 70,000 MW (obtained from Polysciences, Warrington, PA; 75 grams of a 30.5 wt. % solution in water, 0.532 amine equivalents) was charged to a 500 mL polypropylene bottle. O-methylisourea hemisulfate (16.38 grams, 0.133 equivalents) was dissolved in deionized water (100 mL), and the resulting solution was poured into the bottle containing the PEI. The bottle was sealed and placed on a mechanical roller, and the contents were mixed at ambient temperature for approximately 22 hours. Analysis by NMR spectroscopy showed conversion to the desired product, with 25% of the amine groups of the PEI converted to guanidine (predominantly primary amine groups). The mixture was titrated to approximately pH 7 using concentrated hydrochloric acid (measured using pH paper). The percent solids was determined to be 20.5% using an Ohaus moisture balance (Model No. MB35 obtained from Ohaus Corporation, Parsippany, NJ).

Preparatory Example 2. 20% Guanylated Polyethyleneimine (20% G-PEI)
The same procedure as reported in Preparatory Example 1 was followed, except that 13.30 g of O-methylisourea hemisulfate dissolved in 75 mL of deionized water was used to prepare PEI in which 20% of the amine groups were converted to guanidine. The percent solids was determined to be 23.0%.

Preparatory Example 3. 15% Guanylated Polyethyleneimine (15% G-PEI)
The same procedure as reported in Preparatory Example 1 was followed, except that 9.83 g of O-methylisourea hemisulfate dissolved in 50 mL of deionized water was used to prepare PEI in which 15% of the amine groups were converted to guanidine. The percent solids was determined to be 26.0%.

Preparatory Example 4. 10% Guanylated Polyethyleneimine (10% G-PEI)
Polyethyleneimine (PEI), 70,000 MW (50 grams of a 30.0 wt. % solution in water, 0.349 amine equivalents) was charged to a 125 mL polypropylene bottle. O-methylisourea hemisulfate (4.29 grams, 0.0349 equivalents) was dissolved in deionized water (40 mL), and the resulting solution was poured into the bottle containing the PEI. The bottle was sealed and placed on a mechanical roller, and the contents were mixed at ambient temperature for approximately 22 hours. Analysis by NMR spectroscopy showed conversion to the desired product, with 10% of the PEI's amine groups (predominantly primary amine groups) converted to guanidine. The mixture was titrated to approximately pH 7 using concentrated hydrochloric acid (determined using pH paper). The percent solids was determined to be 23.55%.

Preparatory Example 5. 5% Guanylated Polyethyleneimine (5% G-PEI)
The same procedure as reported in Preparatory Example 4 was followed, except that 2.14 grams (g) of O-methylisourea hemisulfate dissolved in 40 mL of deionized water was used to prepare PEI in which 5% of the amine groups were converted to guanidine. The percent solids was determined to be 22.85%.

Preparatory Example 6. 2.5% Guanylated Polyethyleneimine (2.5% G-PEI)
The same procedure as reported in Preparatory Example 4 was followed, except that 1.07 g of O-methylisourea hemisulfate dissolved in 40 mL of deionized water was used to prepare PEI in which 2.5% of the amine groups were converted to guanidine. The percent solids was determined to be 21.7%.

Preparatory Example 7. 1% Guanylated Polyethyleneimine (1% G-PEI)
The same procedure as reported in Preparatory Example 4 was followed, except that 0.429 g of O-methylisourea hemisulfate dissolved in 40 mL of deionized water was used to prepare PEI with 1% of the amine groups converted to guanidine. The percent solids was determined to be 21.2%.

Example 1. 25% G-PEI Coated Nonwoven Fabric Crosslinked with GDGE. A portion (4.88 g) of the 25% guanylated polyethyleneimine from Preparatory Example 1 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. GDGE (0.47 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. The contents of the two bottles were combined and mixed to form the coating formulation. A 10-inch (25.4 centimeters (cm)) x 12-inch (30.5 cm) nonwoven sheet of SONTARA 8004 was weighed prior to coating. The coating formulation (15 mL) was pipetted onto the nonwoven sheet inside a plastic bag. The bag was sealed, and a hand roller was used to press the coating formulation across the nonwoven sheet to ensure even coverage. The coated sheet was removed from the plastic bag and placed on a clean aluminum pan, then dried for 20 minutes at 110° C. The dried coated sheet was weighed and the amount of coating on the sheet was calculated and recorded.

Example 2. 20% G-PEI coated nonwoven fabric cross-linked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.35 g of 20% guanylated polyethyleneimine from Preparatory Example 2.

Example 3. 15% G-PEI Coated Nonwoven Fabric Crosslinked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 3.85 g of 15% guanylated polyethyleneimine from Preparatory Example 3.

Example 4. 10% G-PEI Coated Nonwoven Fabric Crosslinked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.25 g of 10% guanylated polyethyleneimine from Preparatory Example 4.

Example 5. 5% G-PEI coated nonwoven fabric cross-linked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.38 g of 5% guanylated polyethyleneimine from Preparatory Example 5.

Example 6. 2.5% G-PEI coated nonwoven fabric cross-linked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.61 g of 2.5% guanylated polyethyleneimine from Preparatory Example 6.

Example 7. 1% G-PEI coated nonwoven fabric cross-linked with GDGE The same procedure as reported in Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.72 g of 1% guanylated polyethyleneimine from Preparatory Example 7.

Example 8. 20% G-PEI coated nonwoven fabric crosslinked with GDGE (0.5 wt% G-PEI coating formulation)
A portion of the 20% guanylated polyethyleneimine (4.35 g) from Preparatory Example 2 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. GDGE (0.47 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. Each solution of GDGE and G-PEI was diluted 4 times with deionized water. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed. The coating formulation contained 0.5 wt% G-PEI.

Example 9. 20% G-PEI coated nonwoven fabric crosslinked with GDGE (0.1 wt% G-PEI coating formulation)
A portion of the 20% guanylated polyethyleneimine (4.35 g) from Preparatory Example 2 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. GDGE (0.47 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. Each solution of GDGE and G-PEI was diluted 20 times with deionized water. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed. The coating formulation contained 0.1 wt% G-PEI.

Comparative Example 1. 25% G-PEI Coated Nonwoven Crosslinked with BUDGE. A portion (4.88 g) of the 25% guanylated polyethyleneimine from Preparatory Example 1 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. BUDGE (0.46 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. The contents of the two bottles were combined and mixed to form the coating formulation. A 10-inch (25.4 centimeters (cm)) x 12-inch (30.5 cm) nonwoven sheet of SONTARA 8004 was weighed prior to coating. The coating formulation (15 mL) was pipetted onto the nonwoven sheet inside a plastic bag. The bag was sealed, and a hand roller was used to press the coating formulation across the nonwoven sheet to ensure even coverage. The coated sheet was removed from the plastic bag and placed on a clean aluminum pan, then dried for 20 minutes at 110° C. The dried coated sheet was weighed and the amount of coating on the sheet was calculated and recorded.

Comparative Example 2. 20% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.35 g of 20% guanylated polyethyleneimine from Preparatory Example 2.

Comparative Example 3. 15% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 3.85 g of 15% guanylated polyethyleneimine from Preparatory Example 3.

Comparative Example 4. 10% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.25 g of 10% guanylated polyethyleneimine from Preparatory Example 4.

Comparative Example 5. 5% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.38 g of 5% guanylated polyethyleneimine from Preparatory Example 5.

Comparative Example 6. 2.5% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.61 g of 2.5% guanylated polyethyleneimine from Preparatory Example 6.

Comparative Example 7. 1% G-PEI Coated Nonwoven Fabric Crosslinked with BUDGE The same procedure as reported in Comparative Example 1 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.72 g of 1% guanylated polyethyleneimine from Preparatory Example 7.

Comparative Example 8. 25% G-PEI Coated Nonwoven Fabric Crosslinked with EGDGE A portion (4.88 g) of the 25% guanylated polyethyleneimine in Preparatory Example 1 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. EGDGE (0.40 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed.

Comparative Example 9. 20% G-PEI Coated Nonwoven Fabric Crosslinked with EGDGE The same procedure as reported in Comparative Example 8 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.35 g of 20% guanylated polyethyleneimine from Preparatory Example 2.

Comparative Example 10. 15% G-PEI Coated Nonwoven Fabric Crosslinked with EGDGE The same procedure as reported in Comparative Example 8 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 3.85 g of 15% guanylated polyethyleneimine from Preparatory Example 3.

Comparative Example 11. 25% G-PEI Coated Nonwoven Fabric Crosslinked with PEGDGE A portion (4.88 g) of the 25% guanylated polyethyleneimine from Preparatory Example 1 was diluted to 25 g with deionized water in a polypropylene bottle and mixed. PEGDGE (1.15 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed.

Comparative Example 12. 20% G-PEI coated nonwoven fabric cross-linked with PEGDGE. The same procedure as reported in Comparative Example 11 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 4.35 g of 20% guanylated polyethyleneimine from Preparatory Example 2.

Comparative Example 13. 15% G-PEI Coated Nonwoven Fabric Crosslinked with PEGDGE The same procedure as reported in Comparative Example 11 was followed, except that the 25% guanylated polyethyleneimine from Preparatory Example 1 was replaced with 3.85 g of 15% guanylated polyethyleneimine from Preparatory Example 3.

Comparative Example 14. 20% G-PEI coated nonwoven fabric crosslinked with BUDGE (0.5 wt% G-PEI coating formulation)
A portion of the 20% guanylated polyethyleneimine from Preparatory Example 2 (4.35 g) was diluted to 25 g with deionized water in a polypropylene bottle and mixed. BUDGE (0.46 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. Each solution of BUDGE and G-PEI was diluted 4 times with deionized water. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed. The coating formulation contained 0.5 wt% G-PEI.

Comparative Example 15. 20% G-PEI coated nonwoven fabric crosslinked with BUDGE (0.1 wt% G-PEI coating formulation)
A portion of the 20% guanylated polyethyleneimine from Preparatory Example 2 (4.35 g) was diluted to 25 g with deionized water in a polypropylene bottle and mixed. BUDGE (0.46 g) was added to the polypropylene bottle, diluted to 25 g with deionized water, and mixed. Each solution of BUDGE and G-PEI was diluted 20 times with deionized water. The contents of the two bottles were combined and mixed to form the coating formulation. The coating procedure described in Comparative Example 1 was followed. The coating formulation contained 0.1 wt% G-PEI.

Example 10. Wash-Off Assay of G-PEI Coated Nonwovens The coated nonwoven sheets of Examples 1-3, Comparative Examples 1-3, and Comparative Examples 8-13 were washed according to the test method "Wash-Off Assay." The results for the percentage of coating washed off are reported in Table 1 and Figure 2 as the average value obtained from three replicates. The G-PEI coated articles crosslinked with glycerol diglycidyl ether (GDGE) have less wash-off of the coating from the nonwoven sheets after washing (i.e., greater retention of the coating on the nonwoven sheets) compared to the use of BUDGE, EGDGE, and PEGDGE.

Example 11. Wash-Off Assay of G-PEI Coated Nonwovens The coated nonwoven sheets of Examples 4-7 and Comparative Examples 4-7 were washed according to the test method "Wash-Off Assay." The results for the percentage of coating washed off are reported in Table 2 and Figure 3 as the average value obtained from three replicates. The G-PEI coated articles crosslinked with glycerol diglycidyl ether (GDGE) have less wash-off of the coating from the nonwoven sheets after washing (i.e., greater retention of the coating on the nonwoven sheets) compared to using GDGE for crosslinking.

Example 12. Tartrazine Static Binding Capacity of G-PEI Coated Nonwovens. The coated nonwoven sheets of Examples 1-3 and Comparative Examples 8-13 were washed according to the test method "Wash-Off Assay." An uncoated nonwoven sheet was also washed and served as an experimental control. Each sheet was challenged with a 1 mg/mL tartrazine dye solution according to the "Tartrazine Static Binding Capacity Assay" described in the Test Methods section. The static binding capacity results are shown in Table 3 and Figure 4. The washed nonwovens challenged with tartrazine showed that G-PEI crosslinked with GDGE had a significantly higher static binding capacity (SBC) compared to crosslinks with BUDGE, EGDGE, and PEGDGE. These results indicate a higher binding capacity due to the increased level of crosslinked polymer matrix using GDGE over other polyglycidyl ethers after the coating and washing process.

Example 13. Microbial Removal and Transfer Using G-PEI Coated Nonwoven Sheets The coated nonwoven sheets of Examples 8-9 and Comparative Examples 14-15 were evaluated as wipes for removing microorganisms from surfaces using the "Test Method for Removal of Microorganisms and Transfer of Contaminants from Microbially Contaminated Surfaces" described in the Test Methods section. An uncoated nonwoven sheet was also evaluated as an experimental control. The results of removal of spores of Clostridium sporogenes (C. sporogenes) ATCC #3584 from surfaces and cross-contamination using the coated nonwoven sheets as wipes are reported in Tables 4-5 and Figures 5-6. Results are reported as the average value obtained from three replicates.

Evaluation of Examples 1-3 and Comparative Example 3 as wipes showed no difference in bacterial spore removal from surfaces (data not shown). These examples were coated from a 2 wt% G-PEI solution with enough crosslinker to react with 20% amine. By reducing the initial polymer and crosslinker concentrations by 4-fold (0.5 wt% G-PEI solution) and 20-fold (0.1 wt% G-PEI solution), Examples 8-9 were shown to increase bacterial spore removal and reduce surface-to-surface migration of those spores compared to Comparative Examples 14-15. The results demonstrate a clear advantage of using GDGE to crosslink at low polymer concentrations.

The entire disclosures of the patents, patent documents, and publications cited herein are incorporated by reference in their entirety, as if each were individually incorporated. In the event of any conflict or inconsistency between the description herein and the disclosure of any document incorporated herein by reference, the description herein shall control. Various modifications and alterations to the present disclosure will become apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. It is understood that the present disclosure is not intended to be unduly limited by the exemplary embodiments and examples described herein, and that such examples and embodiments are presented merely as examples within the scope of the present disclosure, which is intended to be limited only by the claims set forth herein as follows.

Claims (10)

An article,
A substrate;
a cationic coating bound to the substrate, the cationic coating comprising a guanidinyl-containing polymer crosslinked on the substrate;
The guanidinyl-containing polymer has the following formula (I):
[In the formula,
^R3 is H, _C1 - _C12 (hetero)alkyl, _C5 - _C12 (hetero)aryl, or a polymer;
each ^R4 is independently H, _C1 - _C12 (hetero)alkyl, or _C5 - _C12 (hetero)aryl;
each R ⁵ is H, C ₁ -C ₁₂ (hetero)alkyl, C ₅ -C ₁₂ (hetero)aryl, or N(R ⁴ ) ₂ ;
The polymer is the remainder of an amino polymer chain,
m is 1 or 2;
x is an integer of at least 1.
It is of
The article wherein the guanidinyl-containing polymer is crosslinked with an amine-reactive polyepoxy compound having pendant --OH groups. 10. The article of claim 1, wherein the guanidinyl-containing polymer is crosslinked by reaction of 5 mole % to 50 mole % of the amino groups of an amino polymer precursor with the amine-reactive polyepoxy compound having pendant --OH groups. 3. The article of claim 1 or 2, wherein the amine reactive polyepoxy compound having pendant -OH groups is selected from the group of glycerol diglycidyl ether, sorbitol diglycidyl ether, diglycerol diglycidyl ether, diglycerol triglycidyl ether, pentaerythritol diglycidyl ether, pentaerythritol triglycidyl ether, trimethylolpropane diglycidyl ether, trimethylolethane diglycidyl ether, and combinations thereof. The article of claim 3 , wherein the amine-reactive polyepoxy compound having pendant -OH groups is glycerol diglycidyl ether. The article of any one of claims 1 to 4 , wherein 0.1 mol % to 95 mol % of the amino groups of the amino polymer precursor are functionalized with guanidinyl groups. The article of any one of claims 1 to 5 , wherein the amino polymer is selected from the group consisting of polyaminoamides, polyamidoamines, polyethyleneimines, polypropyleneimines, polyvinylamines, polyallylamines, polydiallylamines, and mixtures thereof. 7. The article of claim 6 , wherein the amino polymer is polyethyleneimine , the precursor of which has up to 25 mole percent of the amino groups functionalized with guanidinyl groups . The article of any one of claims 1 to 7 , wherein the substrate is porous. 9. The article of claim 8 which is a wipe. 10. A method of removing contaminants from a contaminated surface, the method comprising contacting the wipe of claim 9 with an area of the contaminated surface in the presence of a liquid, wherein the contaminated surface is a solid surface.